I brought my rifle a few weeks ago to get the barrel threaded and a F/S installed.(thread posted eariler)
Well, went to the range today to site in my new scope and guess what? Damn rifle would not cycle at all, the bolt did not move a bit, the empty shell just stay in the chamber.
I talked to the guys there and they checked the gas tube for leaks and proper placement. They seem to think it a major gas leak in the barrel or front site.
So, I brought it back to the shop that installed the F/S and they said they didnt do anything with the gas system(would think you have to install thread the barrel) and the gun was defective and sent it back to Bushmaster?

 What do you guys think?

          Bri

P.S. The gun is close to new with only 250 rounds shot and it was fine when I brought it in to be threaded.

Check the key on top of the bolt carrier. Make sure that the allen screws are tight.

Did it work before you took it to the gunsmith?  I know my first upper build I put the damn gas tube in upside down and the bolt didn't move a bit (I guess that's what happens when no gas gets to the bolt!).

Spooky

P.S. The gun is close to new with only 250 rounds shot and it was fine when I brought it in to be threaded.

the gun was defective and sent it back to Bushmaster

It worked before you gave it to the 'gunsmith' and now it doesn't...  I doubt it's somehow suddenly defective, the problem is what did they do to it and now don't want to admit?

With the type of failure you've described, I'd check to see if the gas tube is in upside down <most likely> or if you have a complete blockage of the gas tube, gas port, or carrier key caused by debris from the threading process.

If you don't already have it, download the -23 manual by right clicking the link below and selecting 'save link as'...

ar15.com/content/manuals/TM9-1005-319-23.pdf

...and I'd certainly avoid sending any more work to whoever you used...  Keep us posted...

 All your guys suggestions are what the men at the gun range said. but when I brought back to the shop that did the threading, they were very quick on saying it was defective and they had "nothing " to do thing the gas systemhat
I'm willing to bet that they are not even going to send it to B/M, I think it will go back to the gunsmith to have to fix his screw-up and say Bushmaster fixed it.

I will be calling Bushmaster to see if is or was there for a repair, Wish me luck!!!

                                      Brian